Urethane adhesives are known in the art. U.S. Pat. No. 4,318,837 describes a urethane adhesive composition consisting of 100 parts of a saturated polyester and 5 to 150 parts of unsaturated a polyester containing 5 to 15 parts of an organic polyisocyanate, which is suitable for adhering wood to vinyl film. U.S. Pat. No. 4,323,491 discloses a urethane adhesive composition comprising a prepolymer of polydiethylene glycol adipate and tolylene diisocyanate, polyisocyanate, trichloroethylphosphate, and a mixture of water, urea, and sodium sulphoricinate, the object being to upgrade the strength of an adhesive joint at negative temperatures and reduce the reactive volatile components in the adhesive composition. U.S. Pat. No. 4,698,408 discloses a two component adhesive system comprising a mixture of an isocyanate prepolymer and a polyepoxide and a mixture of a polyol, a urethane curing catalyst and an epoxy curing catalyst, the stated advantages of such a system being significantly improved high temperature thermal stability and immediate nonsagging behavior. U.S. Pat. No. 4,748,781 describes a method of bonding structural support channels to a panel using a polyurethane adhesive foam which among other advantages provides resistance to heat flow.